35．The flood and infection ____ brought along really made the villagers suffer a lot.

A．what　　　　 　　　 B．that　　　 　　C．which　　　 　D．it

34．Although he knew little about the large amount of work done in the field , he succeeded 　　　　　other more well-informed experimenters failed .

A．which 　　　 　　　　　 B．that 　 　　　　 C．what 　　　　 D．where

33．　　　　 　the people have become masters of their country　　　　 　science can really serve the people.

A．It is only then; that　　　　 B．It was that; when

C．It is only when; that　　　　　D．It was when; then